Differential pressure-gage.



No. 638,052. Patented Nov; 28, I899. C. B. HEINTZ.

DIFFERENTIAL PRESSURE GAGE.

(Application mm Sept. 19, 1899.)

(No Model.)

W/TNE SSE S ma cams Psvcxs w. mowumo. WASHINGTON, n c

UNITED STATES PATENT OFFICE.

CHARLES B. HEINTZ, OF CLEVELAND, OHIO.

DIFFERENTIAL PRESSURE-GAG E.

SPECIFICATION forming part of Letters Patent No. 638,052, dated November28, 1899.

Application filed $eptember 19, 1899. Serial No. 780,982. (No model.)

To (ZZZ whmn it may concern:

Be it known that 1, CHARLES E. HEINTZ, of Cleveland, in the county ofOuyahoga and State of Ohio, have invented a new and ImprovedPressure-Indicator, of which the following is a full, clear, and exactdescription.

The object of the invention is to provide a new and improvedpressure-indicator for use on engines, cylinders, pumps, and otherapparatus for accurately indicating the pressure at both ends of thecylinder or in the two pump-chambers, so that in case of variation inpressure existing errors can be rectified by making necessaryadjustments in the valves, &c.

The invention consists of novel features and parts and combinations ofthe same, as Will be fully described hereinafter and then pointed out inthe claims.

A practical embodiment of my invention is represented in theaccompanying drawings, forming a part of this specification, in whichsimilar characters of reference indicate corresponding parts in both theviews.

Figure 1 is a sectional side elevation of the improvement, and Fig. 2 isan enlarged transverse section of the same on the line 2 2 in Fig. 1.

The improved pressure-indicator is connected by pipes A A with the endsof cylinders or other apparatus, and the said pipes are connected bycouplings B B with a tube or cylinder O, as is plainly indicated in Fig.

1. In the said tube or cylinder 0, at or near the ends thereof, aremounted to slide pistons D D, normally resting at their outer endsagainst pins E E,respective1y, held in the tube or cylinder 0. The inneror opposite faces of the pistons D D are pressed on by springs F F,coiled in the tube 0, their inner 'ends being attached to ablock G andhaving movement in the tube lengthwise thereof, a pointer H extendingfrom the block through a longitudinally-extending slot 0, formed in themiddle portion of the tube or cylinder 0. The pointer II indicates on agraduation I, having zero at the middle, as shown in Fig. 1. Now by theconstruction described and shown in Fig. 1 the fluid under pressure canpass freely from the'ends of the cylinder by way of the pipes A A intothe outer ends of the tube or cylinder 0 to exert pressure against thecorresponding pressure-piston D or D. The latter are now forced towardeach other by the pressure exerted by the fluid, so that the springs F Fare compressed, and in case the pressure of the fluid acting on thepistons varies then one spring is more compressed than the other, andthe preponderance of pressure causes a shifting of the pointer II to theright or the left of zero, according to which of the pistons I) or D issubjected to the higher pressure-that is, if the piston D is subjectedto the higher pressure then the block G is moved to the right and thepointer I-I indicates the difference in pressure on the graduation I atthe right of the zero-mark, and in case' the pressure is highest on thepiston D then the pointer I-I moves to the left of the zero-mark toindicate the difference in pressure. In case the pressure is equal onboth pistons D D then they move like distances with corresponding equalpressure on their springs F F, so that the pointer H remains at zero onthe graduation I. Thus the user of the apparatus can readily see at aglance whether there is a difference of pressure in the two ends of thecylinder or not, and if there is a difference the pointer H indicates atwhat end of the cylinder the preponderance of pressure is, and theamount thereof is shown by the pointer on the graduation I. From theforegoing it is also evident that the indicator also shows the slightestback pressure in the cylinder, as the pointer H cannot go back to zerounless the pressure ceases or is equal in both ends of the cylinder. Thepins E E are preferably made tapering and drawn tight by nuts, so as toprevent leakage of pressure at the seats of the pins in the tube O. Thepins E E are sufficiently small to leave sufficient space for the fluidsto reach the outer faces of the pistons D D. It is expressly understoodthat I do not limit myself to the special use of the device onengine-cylinders, as it is evident that the apparatus may be employed onpumps and other apparatus for indicating the variation of pressure intwo chambers or parts.

Having thus fully described my invention, I claim as new and desire tosecure by Letters Patent 1. A pressure-indicator comprising a tubeadapted to be connected at its ends with dif ferent pressu re-supplies,pistons fitted to slide in said tube, springs pressing said pistonstoward the ends of the tube, and a pointer for indicating variation ofpressure against each piston, as set forth.

2. A pressure-indicator, comprising a tube adapted to be connected atits ends with different pressure-supplies, pistons fitted in said tube,a spring interposed between said pistons and tending to press thepistons away from each other, and a pointer for indicating variation ofpressure against each piston, as set forth.

3. A pressure-indicator, comprising a tube connected at its ends withdifferent pressure supplies, pistons mounted to slide in the said tube,springs pressing the said pistons on the faces opposite Where thepressures act on the GHARLES B. HEINTZ.

lVitnesses:

MICHAEL STAEBLER, HENRY HOWARTH.

